This patch makes update-index --refresh write the index if it contains racy
timestamps, as discussed at [1].

Changes since v1:

 * main commit message now uses 'git update-index' and the paragraph was
   dropped
 * t/t7508-status.sh: two tests added which capture status racy handling
 * builtin/update-index.c: comment improved
 * t/t2108-update-index-refresh-racy.sh: major overhaul
   * one test case added
   * mtime-manipulations simplified and aligned to t7508
   * code style fixes, as discussed

[1]
https://lore.kernel.org/git/d3dd805c-7c1d-30a9-6574-a7bfcb7fc013@syntevo.com/

Marc Strapetz (2):
  t7508: add tests capturing racy timestamp handling
  update-index: refresh should rewrite index in case of racy timestamps

 builtin/update-index.c               | 11 +++++
 cache.h                              |  1 +
 read-cache.c                         |  2 +-
 t/t2108-update-index-refresh-racy.sh | 64 ++++++++++++++++++++++++++++
 t/t7508-status.sh                    | 28 ++++++++++++
 5 files changed, 105 insertions(+), 1 deletion(-)
 create mode 100755 t/t2108-update-index-refresh-racy.sh

base-commit: dcc0cd074f0c639a0df20461a301af6d45bd582e

Submitted-As: https://lore.kernel.org/git/pull.1105.v2.git.1641388523.gitgitgadget@gmail.com
In-Reply-To: https://lore.kernel.org/git/pull.1105.git.1640181390841.gitgitgadget@gmail.com